Integrate support for xen in to i386 common code.

MFC after:	1 month

1 files changed, 96 insertions, 0 deletions

diff --git a/sys/i386/i386/sys_machdep.c b/sys/i386/i386/sys_machdep.c
index 97ebe3477be4..f792f2a5d2a6 100644
--- a/sys/i386/i386/sys_machdep.c
+++ b/sys/i386/i386/sys_machdep.c
@@ -58,6 +58,20 @@ __FBSDID("$FreeBSD$");
 
 #include <security/audit/audit.h>
 
+#ifdef XEN 
+#include <machine/xen/xenfunc.h>
+
+void i386_reset_ldt(struct proc_ldt *pldt); 
+
+void 
+i386_reset_ldt(struct proc_ldt *pldt) 
+{ 
+        xen_set_ldt((vm_offset_t)pldt->ldt_base, pldt->ldt_len); 
+} 
+#else  
+#define i386_reset_ldt(x) 
+#endif 
+
 #include <vm/vm_kern.h>		/* for kernel_map */
 
 #define MAX_LD 8192
@@ -164,7 +178,12 @@ sysarch(td, uap)
 			 */
 			sd.sd_lobase = base & 0xffffff;
 			sd.sd_hibase = (base >> 24) & 0xff;
+#ifdef XEN
+			/* need to do nosegneg like Linux */
+			sd.sd_lolimit = (HYPERVISOR_VIRT_START >> 12) & 0xffff;
+#else			
 			sd.sd_lolimit = 0xffff;	/* 4GB limit, wraps around */
+#endif
 			sd.sd_hilimit = 0xf;
 			sd.sd_type  = SDT_MEMRWA;
 			sd.sd_dpl   = SEL_UPL;
@@ -174,7 +193,12 @@ sysarch(td, uap)
 			sd.sd_gran  = 1;
 			critical_enter();
 			td->td_pcb->pcb_fsd = sd;
+#ifdef XEN
+			HYPERVISOR_update_descriptor(vtomach(&PCPU_GET(fsgs_gdt)[0]),
+			    *(uint64_t *)&sd);
+#else
 			PCPU_GET(fsgs_gdt)[0] = sd;
+#endif
 			critical_exit();
 			td->td_frame->tf_fs = GSEL(GUFS_SEL, SEL_UPL);
 		}
@@ -194,7 +218,13 @@ sysarch(td, uap)
 			 */
 			sd.sd_lobase = base & 0xffffff;
 			sd.sd_hibase = (base >> 24) & 0xff;
+
+#ifdef XEN
+			/* need to do nosegneg like Linux */
+			sd.sd_lolimit = (HYPERVISOR_VIRT_START >> 12) & 0xffff;
+#else	
 			sd.sd_lolimit = 0xffff;	/* 4GB limit, wraps around */
+#endif
 			sd.sd_hilimit = 0xf;
 			sd.sd_type  = SDT_MEMRWA;
 			sd.sd_dpl   = SEL_UPL;
@@ -204,7 +234,12 @@ sysarch(td, uap)
 			sd.sd_gran  = 1;
 			critical_enter();
 			td->td_pcb->pcb_gsd = sd;
+#ifdef XEN
+			HYPERVISOR_update_descriptor(vtomach(&PCPU_GET(fsgs_gdt)[1]),
+			    *(uint64_t *)&sd);
+#else			
 			PCPU_GET(fsgs_gdt)[1] = sd;
+#endif
 			critical_exit();
 			load_gs(GSEL(GUGS_SEL, SEL_UPL));
 		}
@@ -360,6 +395,10 @@ set_user_ldt(struct mdproc *mdp)
 	}
 
 	pldt = mdp->md_ldt;
+#ifdef XEN
+	i386_reset_ldt(pldt);
+	PCPU_SET(currentldt, (int)pldt);
+#else	
 #ifdef SMP
 	gdt[PCPU_GET(cpuid) * NGDT + GUSERLDT_SEL].sd = pldt->ldt_sd;
 #else
@@ -367,6 +406,7 @@ set_user_ldt(struct mdproc *mdp)
 #endif
 	lldt(GSEL(GUSERLDT_SEL, SEL_KPL));
 	PCPU_SET(currentldt, GSEL(GUSERLDT_SEL, SEL_KPL));
+#endif /* XEN */ 
 	if (dtlocked)
 		mtx_unlock_spin(&dt_lock);
 }
@@ -385,6 +425,44 @@ set_user_ldt_rv(struct vmspace *vmsp)
 }
 #endif
 
+#ifdef XEN
+
+/* 
+ * dt_lock must be held. Returns with dt_lock held. 
+ */ 
+struct proc_ldt * 
+user_ldt_alloc(struct mdproc *mdp, int len) 
+{ 
+        struct proc_ldt *pldt, *new_ldt; 
+ 
+        mtx_assert(&dt_lock, MA_OWNED); 
+        mtx_unlock_spin(&dt_lock); 
+        MALLOC(new_ldt, struct proc_ldt *, sizeof(struct proc_ldt), 
+                M_SUBPROC, M_WAITOK); 
+ 
+        new_ldt->ldt_len = len = NEW_MAX_LD(len); 
+        new_ldt->ldt_base = (caddr_t)kmem_alloc(kernel_map, 
+                round_page(len * sizeof(union descriptor))); 
+        if (new_ldt->ldt_base == NULL) { 
+                FREE(new_ldt, M_SUBPROC); 
+                return NULL; 
+        } 
+        new_ldt->ldt_refcnt = 1; 
+        new_ldt->ldt_active = 0; 
+ 
+        if ((pldt = mdp->md_ldt)) { 
+                if (len > pldt->ldt_len) 
+                        len = pldt->ldt_len; 
+                bcopy(pldt->ldt_base, new_ldt->ldt_base, 
+                    len * sizeof(union descriptor)); 
+        } else { 
+                bcopy(ldt, new_ldt->ldt_base, PAGE_SIZE); 
+        } 
+        pmap_map_readonly(kernel_pmap, (vm_offset_t)new_ldt->ldt_base, 
+                          new_ldt->ldt_len*sizeof(union descriptor)); 
+        return new_ldt; 
+} 
+#else
 /*
  * dt_lock must be held. Returns with dt_lock held.
  */
@@ -423,6 +501,7 @@ user_ldt_alloc(struct mdproc *mdp, int len)
 	
 	return (new_ldt);
 }
+#endif /* !XEN */
 
 /*
  * Must be called with dt_lock held.  Returns with dt_lock unheld.
@@ -667,7 +746,23 @@ again:
 		td->td_retval[0] = uap->start;
 	return (error);
 }
+#ifdef XEN
+static int
+i386_set_ldt_data(struct thread *td, int start, int num,
+	union descriptor *descs)
+{
+	struct mdproc *mdp = &td->td_proc->p_md;
+	struct proc_ldt *pldt = mdp->md_ldt;
 
+	mtx_assert(&dt_lock, MA_OWNED);
+
+	/* Fill in range */
+	bcopy(descs,
+	    &((union descriptor *)(pldt->ldt_base))[start],
+	    num * sizeof(union descriptor));
+	return (0);
+}
+#else
 static int
 i386_set_ldt_data(struct thread *td, int start, int num,
 	union descriptor *descs)
@@ -683,6 +778,7 @@ i386_set_ldt_data(struct thread *td, int start, int num,
 	    num * sizeof(union descriptor));
 	return (0);
 }
+#endif /* !XEN */
 
 static int
 i386_ldt_grow(struct thread *td, int len)